Though I bear record of myself, yet my record is true. — For “record” read in each instance witness, as in John 8:13. The pronoun is emphatic. “Even if I do bear witness of Myself, yet My witness is true.” He had before quoted their law of evidence (John 5:31), and showed that He fulfilled its canons. He is about to show this again (John 8:17-18), but He claims first that in reality the law cannot apply to Him. They claim a human proof of that which transcends human knowledge. They claim the evidence of a witness, to a truth for which there could not possibly be a human witness.
For I know whence I came, and whither I go. — The requirement of two witnesses was based on the imperfection of individual knowledge, and the untrustworthiness of individual veracity. His evidence, as that of One who knew every circumstance affecting that of which He testified, was valid, for the perfection of His knowledge implied that He was divine. He and He only of all who have appeared in human form, knew the origin and issue of His life; He and He only knew the Father’s home from which He came, and to which He was about to return. For the same words, “I go,” or, I go away, as applied to His voluntary death, comp. John 7:33.
But ye cannot tell whence I come, and whither I go. — The Greek word for “cannot tell” is the same as that for “know” in the previous clause. For “and” most of the better MSS. read or. Making these corrections we have, But ye know not whence I come, or whither I go. The change of tense is to be noted. Speaking of His own knowledge, He refers to the Incarnation in the historic past, “I came.” Speaking of their continued ignorance, He refers to the coming as continuing in the present. Every renewed act and word was a coming to them from God. (See John 3:31.) He knew, in the fulness of knowledge, the whence of past coming and the whither of future going. They knew neither the one nor the other. They do not even know His present mission. Once again His present teaching takes up words uttered before. They had said, “When the Christ cometh no man knoweth whence He is” (John 7:27). He has, then, fulfilled their test. He had said, “Ye both know Me, and do know whence I am” (John 7:28); but that knowledge was of the earthly life only, and He now speaks to them of heaven.